Gun Cache: MonoVault Gun Burial Tube

Categories: Survival Gear


gun burial tube feature
The smallest MonoVault is big enough to hold spare ammo, MREs, a flask, full-size 9mm, and the precious Prepper Press squirrel.

While the MonoVault gun burial tube is no longer being produced, there are other gun cache containers available on the market that are comparable in size and come at a much lower cost. This article covers the ins and out of underground storage containers for guns including the MonoVault, HQ Issue, and other cache containers.

Table of Contents

Underground Storage Containers for Guns

Whenever the headlines carry news of a possible new law that might limit 2nd Amendment rights, conversations will often come around to the subject of burying guns. There are different schools of thought on this, but if you’re reading this article, it’s because you are at least curious about the subject.

I’ll cover the most common off-the-shelf products people have purchased for this purpose, but it is important that you read the section below about the legality of burying guns.

Of course, underground caches are not just for guns, and what applies to firearms also applies to survival caches of all types. If not firearms, people might want to bury their prepper silver, cash, bulk ammo, important documents, USB with important files, implementing a secondary survival cache, even caching food storage or fuel on the path to bugging out.

HQ Issue Gun Burial Tubes

The product and pictures in this article focus on the MonoVault Burial Tubes. MonoVault is no longer in business, so all online listings of the products featured here are listed as “out of stock.” Fear not, HQ Issue has filled the hole (no pun intended).

HQ Issue gun burial tube
The large HQ Issue gun burial tube.

Unlike the MonoVaults that follow, the HQ Issue comes in one size – large. This means fewer options, but the upside of this is HQ Issue is able to offer a similar product at a much lower price. For example, the large HQ Issue burial tube costs only about $30 more than what the smallest MonoVault used to cost. In fact, a MonoVault of the HQ size (MonoVault 248) sold for more than twice as much as the HQ Issue.

Compare prices for the HQ Issue:

HQ Issue Burial Tube Product Specifications

  • constructed of polymer plastic,
  • waterproof, and
  • like the MonoVaults, includes an O-ring seal, gamma lid, and secondary cover.

This is a big tube measuring in at 12″ wide and 45.38″ tall (interior dimensions). It has a circumference of 40.5″.

The upside to a container this size is that it will hold a lot of stuff. The downside is that you will have to spend some more time digging a deep enough hole. A shovel and post-hole digger are requirements to get this into the ground. Once you go this deep, however, plan to leave it there. Digging it out would probably be worse than putting it in.

Other Gun Cache Containers

You are not restricted to specified “gun cache containers,” of course. There are plenty of other underground storage containers that will accommodate your cache. The most obvious alternative is the time capsule, but really, any product that is of solid construction as is specifically designed to keep water and moisture out will be fine. Aim for plastic or stainless steel.

Here are some other product choices. They are not big enough to accommodate a long gun, such as the HQ Issue or MonoVault, but they are perfect for smaller caches of essential survival equipment or valuables.

MTM SAC Survivor Ammo Can – This is a cheap option, but it is only 10.25 x 10.25 x 11.5″ in size. Small, but big enough to as a small gun cache container. It will hold ammunition, cash or silver, survival equipment, etc.

Stainless Steel Waterproof Storage Container – The listed lifetime of this unit is 200 years, plenty long enough to store whatever you hope to retrieve in your – or your kid’s – lifetime. Made of SUS 304 stainless steel, it measures in at 13.5 x 6.4 x 5.9″. For the price, that makes it a very small for the money and not that practical for storing a survival cache. Some may find it of use, however.

Large” Stainless Steel Waterproof Storage Container – This unit is same as the above, only a bit bigger and nearly twice the cost. The larger size makes it more practical, but it is still designed more as a small time capsule product than an actual product used by preppers to store large amounts of gear underground.

Because the market is not very well supplied for long-term underground survival cache containers or gun burial tubes, today’s prepper is pretty much left to the HQ Issue described above. It’s unfortunate that MonoVault tubes are no longer available because they came in so many different sizes.

Take a look at what used to be available, and then read past it for a note about legality, burying the tube, and digging it up.

MonoVault Gun Burial Tubes

Guns, ammo, gear, precious metals, and most anything you deem necessary can be buried in a variety of different containers, the extent to which goes beyond the scope of this post. Here we’re focusing on one type of container, the MonoVault.  The MonoVault is a ready-to-bury storage tube. Constructed of a one-piece molded body, there are no joints along the sides or on the bottom that could leak.

This type of product represents the simplest, fastest, most convenient way to get your goods safely in the ground. Looking like a large PVC pipe with sealed ends, it functions in much the same way. While the tubes do not come cheap, once one goes about pricing similarly-sized PVC pipes, and factors in the value of one’s time, there’s a new appreciation and understanding of the pricing, and the product itself.

The tubes come in a variety of different sizes, and all function in the same manner, but for purposes of this post, we’ll be looking at three in particular: the 110s, 130s, and 248s. Each has similar construction, coming in either black or olive drab. The “s” denotes standard wall construction of 1/4”. The top of the containers have a large-mouth spin-on lid with o-ring seal, and atop that sits another cover, the “Burial Shield,” that looks much like the top of a landmine.

The 110s has an inside diameter of 9 3/4” and an inside depth of 7 1/2”. The 130s has a diameter of 9 3/4” and a depth of 23 3/8”. The Mono Vault 248 has a whopping diameter of 12 1/4” and a depth of 45”!  Dimensions, diameter, and depth – blah, blah, blah. The real question here is – how much stuff can you cram into these things?

MonoVault 248 Storage

Well, we found out.  This is the Mono Vault 248 with everything we crammed into it:

  1. A mid-length AR with collapsible stock, five 30-round magazines, and 1,075 rounds of 5.56,
  2. A Ruger 10/22 and 1,275 rounds of .22lr,
  3. A Remington 870 shotgun and eighty 12-gauge shotgun shells,
  4. A S&W Shield with spare magazine and 450 rounds of 9mm,
  5. A crank-powered radio,
  6. A Buckmaster knife,
  7. Small pair of binoculars,
  8. A small bag of various “survival” tools (fire-making products, few first aid products, etc.),
  9. Small solar panels for charging batteries, and
  10. #10 Can of Freeze Dried Food Storage.

Looking into the top with all of this gear, there’s still room for more. If we’d been more careful with the packing, made boxed ammo into loose ammo, we could have easily double the amount of ammo and packed another 45 servings of freeze dried chocolate drink.

MonoVault 130 Storage

For the 130s, we packed what you see pictured:

  1. A mid-length AR with collapsible stock (upper separated from lower), five 30-round magazines, and 925 rounds of 5.56,
  2. A S&W Shield with spare magazine and 450 rounds of 9mm,
  3. A crank-powered radio,
  4. A large survival knife,
  5. Small pair of binoculars,
  6. A small bag of various “survival” tools (fire-marking products, few first aid products, etc.),
  7. Small solar panels for charging batteries, and best of all,
  8. #10 Can of Freeze Dried Food Storage.

MonoVault 110 Storage

For the Mono Vault 110, we packed what you see pictured:

  1. a S&W Shield with spare magazine and 100 rounds of 9mm, and best of all,
  2. #10 Can of Freeze Dried Food Storage.

This is the same container as seen in the very top picture in this article. It’s deeper than it looks and is the perfect size for storing valuables and smaller, high-value goods that you need to keep hidden and safe for retrieval at some future, undetermined date.

Burying Guns – The Law

While I know of no law that would prevent someone from stashing stacks of canned beans and birth certificates, one must be fully aware of the laws in his/her own locale when it comes to burying guns or ammunition. Take the state of Massachusetts, for example:  The law requires guns to be stored in a specific manner.  All guns, when not in use, with the exception of primitive firearms, must be stored or kept “secured in a locked container or equipped with a tamper-resistant mechanical lock or other safety device,” to prevent unauthorized use. Penalties are assessed even if no underage person obtains access (source).

I’m no lawyer, but it’d seem to me that you’d be violating the law if you’re burying guns in Massachusetts. So – stay mindful of the laws in your area if you’re seriously considering the subterranean storage of guns or ammunition. Even if you find it is legal – is it safe or wise to do so? ­What if a stranger discovers it? Could children? Those are questions for you to answer. Stay legal. Stay safe.

Burying Your Hidden Cache Tube

Bury your tube before filling it, or you may be carrying a very heavy tube. 

The makers of the MonoVault write:

Your MonoVault will float. While this is great on the water, it is not so good in burial applications. Clay soils of an excavated hole can inhibit drainage of any water that may collect. Water collected in the hole can impart tremendous floating forces on your MonoVault, driving it to the surface and then some. It is advisable to anchor your vault effectively with appropriate compaction or the addition of hardening or sealing agents. A few sacks of concrete in the clean bottom of your backfill can serve to anchor the vault to the bottom of the hole. Use caution with concrete in the vicinity of the lid as most concretes will shrink as they cure and may cause some distortion of the vault and critical sealing surfaces. Choose your site carefully to avoid natural drainages that may direct water to your vault. Slightly sloped or cresting locations may be best.

Surround the tube with crushed stone before back filling it could offer additional protection. If you’re concerned about the possibility of someone hunting for your cache with a metal detector, you can always throw rusty, scrap metal (old nails, cans, etc.) around the site to help throw people off.

The manufacturer also writes:

In high frost areas where the ground freezes deeper than the cover soil, it may be advisable to cover your MonoVault with a piece of foam insulation below the cover soil and extending a couple of feet out from the perimeter of the vault. This insulation can reduce freezing of the soils around the neck of the Mono Vault and the resulting pressures and possible distortion. Be aware that such insulation can also slow snow melt so don’t use a square piece that will leave an unnatural looking residual snow pile.

buried gun products
A sampling of additional products to protect your stored goods.

The landmine-looking Burial Shield will help direct water away from the lid, and it protects against possible shovel damage as it is being recovered. The shield will keep the lid area clear of dust and dirt that could otherwise enter the tube when you open it, potentially compromising the unit when it’s resealed.

There are additional products you can buy to protect the contents.

Rust Prevention storage bags available for guns, and the same oxygen absorbers that you use for long-term coffee storage will also work wonders for keeping moisture out of your underground storage containers. If you’re feeling really ambitious, you could always use cosmoline on your guns. Just be prepared for dealing with trying to get it all off after the fact.

Marking the Burial Site

Are you going to be able to find it when it’s time? You can identify the site by remembering natural landmarks, making note of them, or by using a portable GPS—just make sure you have good satellite reception. A 10’ difference could mean a whole lot of digging in search for it.

Marking it on a map, the old fashioned way, is always an option, but you’ve seen the old pirate movies, right? Someone inevitably finds a treasure map and goes on a hunt. Would someone find your map?

Any record can be found, however, except the record in your head. If you don’t want to rely on that, mark the location in a GPS, mark it on a map, and take pictures of the location. You’ll find it then.

And remember—never whisper about the location of your cache!

There is an exception to that rule, however… what happens if – heaven forbid – you unexpectedly die. Is what you buried something you would want to leave to family? If so, do they know where to retrieve it? It would be a shame to be staring death in the face and your final thought being that of all your hidden gold being lost forever!

Digging Up Your Cache

If you took all of the correct steps in preparing, burying, and hiding your cache, the contents inside should be good to stay stored for… a lifetime (or longer). When you need to retrieve your valuables, just grab your tactical survival shovel and get to work. Hopefully it’s not the dead of winter or you might need other tools to bust through the frozen ground.

What about you? What would YOU bury? How would you bury it? Let me know in the comments.

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